Azo dyestuff the 1-(2&#39;-chloro)-phenyl-3-methyl-5-pyrazolone-azo-benzene



25 solution a Patented Feb.-" 21, 1928.

UNITED STATES PATENT OFFICE} MAX sc -1mm,

socmrr or RIEHEN, NEAR BASEL, SWITZERLAND, ASSIGNOR To THE rum:

CHEMICAL mmrs'rmr n: BASLE,

OF BASEL, SWITZERLAND.

azo DYESTUEF THE 1-(2'-CHLOR0)-PHENYL-3JIETHYL-S-PYRAZOLONE-AZO-BENZENE.

No Drawing. Application The present invention relates to a new azo dyestufi valuable for the production of, fast tints on acetyl cellulose; It comprises the new product the new dy'estuil. The new dyestufi is obtained by coupling diazo-benzene with 1- (2' chloro) -phenyl-3-methyl-5-pyrazolone corresponds with the formula: 4

I water, soluble in benzene and other organic solvents with yellow coloration yielding on acetyl cellulose, when dyed from an aqueous suspension, beautiful pure yellow tints with excellent properties of fastness.

' .Emample.

5-pyrazolone are; disso rid treated-"with a diazo solution obtained from 4, 6 parts of aniline. Th

' is filtered, washed and the material dyed witlr anddyestufi of the formula:

organic solvents yielding on acetate cellulose, when dyed filed July 19, 1926,Se1'ia1 No. 123,598, and in Switzefland August 1, 1925.

dyestufi that separates in yellhw .flakes and dried. It forms a yellow powder soluble inbenzene with yellow coloration and dyes acetate cellulose properties of fastness. Whatl claim is:

As a'new product the herein described azo soluble in water, soluble in benzene or other with yellow coloration,

from an aqeuous suspension, bea'utiI'ul pure I p I greenish-yellow shades with excellent prop-- 11 parts of 1- (2'-chloro) -phenyl-3-n1ethyl lved in .dilute soda erties of fastness.

In witness whereof I have'hereunto signed my name this 8th day of July. 1926; c MAX S pure greenish-yellow shades with excellent 7 

